Considering the traffic organization project and traffic signal control project of the small and medium-sized cities in China, based on the dynamic optimization theory of operations research, this paper puts forwards the method of optimization design between the traffic organization and the traffic signal control of urban traffic, sets up the frame of the dynamic optimization. The whole design of the dynamic optimization is divided into three stages, the first stage, based on the original traffic organization project, the traffic signal control project is optimized, the second stage, based on the optimized traffic signal control project after the first stage, the traffic organization project is optimized, the third stage, based on the optimized traffic organization project after the second stage, the traffic signal control project is optimized again, finally the best project is got. This paper takes the conference intersection of HuaiRou district for example, gets the dynamic optimization project between the traffic organization and the traffic signal control, and it is found that this method is better than the past methods after the analysis by computer simulation.